Also, output of CO2 from fossil fuels and cement production reached a record 35 billion tonnes, 58 per cent above 1990, the benchmark year for calculating greenhouse-gas levels.

"Based on estimates of economic activity in 2013, emissions are set to rise 2.1 percent in 2013 to reach 36 billion tonnes of CO2," the Global Carbon Project said in its report.

The 2012 and 2013 rates are slightly below the average growth of 2.7 percent annually over the last 10 years.

Carbon dioxide is the principal greenhouse gas and fossil fuels such as coal, oil and gas as well as cement production account for nearly all its man-made emissions.

The report says about four billion tonnes of CO2 come from other sources, including changes to land use.

It says China, the world's number one carbon emitter, accounts for 70 per cent of the global increase in 2012.

Although consumption from renewable sources and hydropower in China grew by a quarter in 2012, coal accounted for 68 per cent of Chinese energy consumption that same year.

Global footprint

Other countries with an increase in CO2 emissions include Japan, Germany and India.

While CO2 emissions fell in the EU and US, coal burning activities rose.

Glen Peters from the Norway's Centre for International Climate and Environmental Research, who contributed to the report says if US emissions continue to decline as in the last five years, then China will emit more than the US on a per capita basis in the period 2020-2025.

Developing countries including China say rich nations should bear most of the burden for warming as they initiated the problem and their emissions per person are much higher than those of poorer economies.

The report says China's per capita emissions are rising fast because of its reliance on coal, which less energy-efficient than other fuels.

"China has had rapid economic growth in the last decades, bringing lasting benefits to its citizens, but this has come at a great cost to the environment," said Peters.

"The conventional view is that China still lags behind developed countries, but China is actually comparable to many developed countries in terms of per capita CO2 emissions."

Per capita emissions are one of the biggest issues in the climate-change arena.

In May, levels of CO2 in the atmosphere briefly exceeded 400 parts per million for the first time since measurements began at the Mauna Loa Observatory in Hawaii.

Some experts fear the world is on track for double the UN target of two degrees Celsius over pre-industrial times - a recipe for worse drought, flood, storm and rising seas.

In her resignation from politics, Kelly O'Dwyer said she feared another miscarriage in Canberra, far from home. Her announcement is shocking for more than just party-political reasons, writes Emma A. Jane.